The latter, of course, are being improved, but more expensive and also extremely sensitive to sulfur. Removing it from gasoline or diesel fuel is a complex and, again, expensive process.
But methane - the one that comes from the wells and pipes into our kitchens, is simple: CH4 and nothing more. It burns out in cylinders, fulfilling the norms of Euro IV. Of course, nitrogen oxides are formed, where without them, if four fifths of the air is nitrogen! But you don’t have to suffer from soot, there is no sulfur either, the converter is relatively cheap and durable. In the exhaust, a quarter less CO2 - the climate effect is softened, the car contributes 80% less to the formation of smog. And the price of gas, despite its rise in price, is extremely attractive.
The West has long understood these advantages and is developing the "gas" infrastructure with might and main. Moreover, the so-called "gas" (propane-butane or liquefied) goes down in history. After all, it is, again, an oil refining product containing a mass of complex hydrocarbons. It is cheaper than gasoline, but not more environmentally friendly.
In Europe, a kilogram of methane (about 1.5 liters of gasoline in terms of energy saturation) costs 67 cents. In terms of - 47 cents per 1 liter instead of 1.2 "gas" euros. It is interesting that the German government promises to maintain this price until … 2020, but does not guarantee anything regarding gasoline and diesel fuel. So stimulate the transition to gas fuel.
WHAT VALENCE IS OPEL?
Cars that can run on gas or gasoline, correctly called dual-fuel. In Europe, the term "bivalent" has taken root, although the words "bifuel", "bipower" are also found. But only cars that consume exclusively gas are called “monovalent”. Although, strictly speaking, all their gasoline counterparts can claim the same rank. More accurately reflects the essence of the matter, the word “bluepower” coined by FIAT (gas burns with a blue flame), invented by FIAT, but only in 2002 such “multiples” were discontinued.
“Monovalent” cars so far are made only by “Opel”. Let's see what had to change in them.
First of all, it was possible to reduce the amount of control software for the injection controller, to simplify and reduce the cost of the whole system by a quarter. For example, exhaust gas recirculation with its pipelines, valves, sensors became unnecessary. It is now easy to get rid of nitrogen oxides with the help of only a lambda control and an "old" converter. By the way, only 4.2 mg of platinum per 1 cm3 of packing was enough for him, and even two times less cells than needed for a gasoline engine.
But the nozzles were developed anew. Firstly, they should work at a fuel pressure of not 3.8, but 8 bar. Secondly, the cross-section of the blocked channel is larger, which means that more powerful solenoids are needed, which nonetheless would not overload the output stages of the controller.
The compression ratio was increased to 12.8, the pistons were replaced with stronger ones - after all, the pressure in the combustion chamber reaches 90 bar. Candles are also unsweetened: for a reliable cold start, you need a powerful spark that quickly “eats” ordinary electrodes. I had to put "platinum" candles.
Self-diagnosis has also become more complicated in the calculation of monitoring the gas economy: pressure and temperature in cylinders, the dispersion of the properties of the gas itself (alas, it is large - up to 15%). If a dangerous defect is discovered, the car … No, it does not die out, it just switches to … gasoline. That's monovalence! True, a 14-liter gas tank serves only as an emergency reserve. By the way, to prevent knocking, the controller will not allow the throttle to fully open. At temperatures below -30 ° C, gas is supplied for start-up, but in other non-emergency cases only gas!
So, the gas Opel Zafira costs 5.3 kg of gas per 100 km, which is energetically equivalent to gasoline 8 l / 100 km. Given the cost of a kilogram of methane - 67 cents, we get a 2.7 times gain! For the sake of it, you can still come to terms with a cruising range of 350 km, especially since more durable (and roomy) production cylinders are already on the way.
WHO IS GAS?
Unlike domestic leaders who are not too caring about the environment, not a single Western politician will allow himself to doubt the importance of environmental programs. And what a trump card in the election campaigns! So they build, for example, gas stations throughout Germany. In 1998 there were 41 of them, in 2004 - already 415, and in 2007 another 600 will be opened. Today, Germans have 20 thousand cars on methane, Italians have twice as many cars, and in Argentina they are already … 740 thousand units! "Livestock" is growing rapidly: according to forecasts, by 2010 the fleet of gas cars in Germany will be 360 thousand cars.
In fairness, we note: in Europe 2.8 million more cars driven on liquefied propane-butane.
The list of companies collecting gas cars on conveyors is extensive (see help). Joined this company and Honda. Civic GX for the markets of the USA and Canada is even equipped with a portable home compressor that can turn a personal garage into a gas gas station! There would only be a counter in the house, otherwise it is already theft.
The list is not limited to the listed brands, cylinders and equipment can be installed on almost any car. It’s just that he will be able to “not really” drive, if only because the compression ratio of the standard motor is small for efficient operation on gas. In “bivalent” cars, they try to maximize the advantages of gas, while maintaining the possibility of a normal ride on gasoline. For example, they slightly increase the compression ratio and recommend only high-octane gasoline. Two programs are sewn into the controller to bring the injection modes for gas and gasoline closer to optimal. An example is the Mercedes-Benz E200 NGT, which is not only the most powerful passenger car, but also does not lose power and dynamics when working on gas. Nevertheless, such cars are likely to be a thing of the past, as soon as the network of gas stations becomes branched, and the “gas mode” is simply not needed.
GAS AT US
In the USSR, the beginning of the use of gas as motor fuel was laid by a resolution of the Council of People's Commissars of 1936. However, the law on mass gasification of Russian transport has not been adopted to this day, being stuck on endless approvals. Not a single plant will launch mass production of gas cars until there is demand. It is constrained by the underdeveloped network of expensive gas stations - no one will undertake to build them for a couple of thousand cars.
However, there are already many who want to convert the car. Small firms work for them. It is possible to remake a VAZ for gas for about 26, 000 rubles, so this operation is beneficial only for high mileage.
GAZ adapted carburetor (but not injection!) Cars for propane-butane. At the VAZ, they are preparing for the dozens series adapted for working on methane (ЗР, 2001, No. 2) with a unified power supply system. The software uses standard gasoline injection units (controller, sensors, etc.) and allows you to adjust the gas supply depending on pressure and temperature, coordinating the work with a leakage control system. Fuel injected gasoline or gas injectors. That is, the car is “bivalent”. To switch from gas to gas and vice versa, the driver presses a button. During a cold start or if the gas runs out, the engine will switch to gasoline automatically.
It is also planned to develop a “monovalent” (single-fuel) engine optimized for gas supply, like Opel’s. To preserve the boot volume and increase the power reserve at one gas station, it is supposed to transfer the cylinders under the floor of the body and pump gas into them under pressure not of 200, but 320 bar. In this car, the compression ratio can be raised to 12.5 to get the most out of clean fuels.
But the answer to the question of whether or not to be a serial Russian gas-filled car should be sought not in Togliatti, but in the center of Moscow: it all depends on the legislators! Thanks to them, a "gas attack" is in full swing in Western Europe.
GASOLINE WASN’T HAPPENED …
The self-running carriage - “Hippomobile” was created long before Benz by Jean-Etienne Lenoir. Her gas engine developed 1.5 hp. at 100 rpm In 1862, the car drove 18 km from Paris to Jeanville in just three hours. What gas burned in a single cylinder? At that time, houses were lit with the so-called lamp gas - it was obtained from coal. The main components are the same methane (about 30%), hydrogen (50%), CO (9%). It turns out that the gas car of Lenoir is the first “hydrogen car” in the world.
EUROPEAN GAS PRODUCERS
Serial "bivalent" European cars
Cars: FIAT-Punto Natural Power, FIAT-Multiple Bipower, Opel Astra 1.6 CNG Caravan, Opel Zafira 1.6 CNG, Mercedes-Benz E200 NGT Compressor, Peugeot Partner Bivalent, Citroen Berlingo Multispace 1.4 GNV”, “Renault Kangoo GNV”, “Ford Focus 1.8 CNG”, “Volvo Bi-Fuel”(in versions S60, S80, V70), “Volkswagen Golf Variant 2.0 Bi-Fuel”.
In 2005, there will appear: Opel Combo CNG and Ford Focus C-max, in 2006 - Volvo V50 and S40, Volkswagen Turan and Volkswagen Caddy.
Light trucks: FIAT-Ducato Bi-Power, FIAT-Doblo Bi-Power; IVECO-Daily CNG, Ford Transit GFI-II-CNG 2, 3l, Mercedes-Benz Sprinter NGT and Ekonik NGT, Peugeot Boxer Bivalent and Partner Cargo Bivalent, Citroen- Jumper Bivalent”and“Berlingo Cargo Bivalent”, “Volkswagen Transporter T4”.
PRO ET CONTRA
Why is methane bad? Even if you compress it to 200 bar, you will need four times more than the gas tank, the volume of cylinders to maintain the power reserve. True, for hydrogen cars, cylinders withstanding 700 bar are already certified. A little more, and this methane deficiency will be overcome.
Methane is lighter than air, so it escapes in the event of leaks. This allows you to park cars even in underground garages, unlike, for example, those working on propane-butane. The latter accumulates at the bottom, forming an explosive and toxic mixture. According to experts, it is natural gas that is the safest fuel. Say, according to the statistics of accidents in the USA, 98, 000 accidents did not cause a fire in cars with gas cylinders.
When working on a methane-air mixture, the engine power is 10-15% lower. But the octane number of gas is 115–130, which means you can play horsepower by designing an engine for methane or at least increasing the ignition timing by seven degrees.
But a pipe should come to a gas filling station, for example, from Russia. That is, the network of gas stations will not be able to reach the same density as for liquid fuel.
